Vulnerability Discussion
A session lock is a temporary action taken when a user stops work and moves away from the immediate physical vicinity of the information system but does not want to log out because of the temporary nature of the absence.
The session lock is implemented at the point where session activity can be determined. Rather than be forced to wait for a period of time to expire before the user session can be locked, the Ubuntu operating systems need to provide users with the ability to manually invoke a session lock so users may secure their session if they need to temporarily vacate the immediate physical vicinity.
Satisfies: SRG-OS-000030-GPOS-00011, SRG-OS-000031-GPOS-00012
Check
Verify the Ubuntu operating system has the "vlock" package installed by running the following command:
$ dpkg -l | grep vlock
If "vlock" is not installed, this is a finding.
Fix
Install the "vlock" package (if it is not already installed) by running the following command:
$ sudo apt-get install vlock